1. Field of the Invention
The present invention relates to a roller D-ring for a seat belt of a vehicle, and, more particularly, to a roller D-ring for a seat belt of a vehicle, in which a roller is simply and conveniently mounted to a D-ring body in accordance with a folded structure of the D-ring body, so that the assembly process is simple and convenient, and the number of constituent elements is reduced.
2. Description of the Related Art
In general, seat belts are installed in the passenger compartment of a vehicle to restrain the driver and passengers in their seats, and thus, to prevent the driver and passengers from being abruptly projected from their seats by an impact generated in the event of a crash.
FIG. 1 is a perspective view illustrating a conventional seat belt of a vehicle.
As shown in FIG. 1, the conventional seat belt, which is installed in the vehicle to protect the occupant during a crash or overturn, includes a webbing 1 to traverse the body of the occupant, a retractor 2 to wind the webbing 1 in a tensed state and to prevent the webbing 1 from being abruptly unwound during a vehicle crash, and a D-ring 3 to guide the webbing 1 during a winding or unwinding operation of the webbing 1 carried out by the retractor 2 such that the webbing 1 moves along the shoulder of the occupant. The conventional seat belt also includes a buckle 4 fixedly mounted to a seat 6 at a position opposite to the D-ring 3 with reference to the occupant, and a tongue 5 arranged at an intermediate portion of the webbing 1 and adapted to be coupled with the buckle 4.
One end of the webbing 1 is fixed to the retractor 2 so that the webbing 1 can be retracted into and protracted from the retractor 2. The other end of the webbing 1 is fixed to a body of the vehicle at the same side as the retractor 2 by an anchor 7.
The buckle 4 is mounted to the seat 6 at a position opposite to the anchor 7 with reference to the seat 6.
When the occupant couples the tongue 4 to the buckle 4 after sitting in the seat 6, the breast and knees of the occupant are restrained by the webbing 1.
A conventional D-ring, which may be used for the seat belt having the above-mentioned structure, is disclosed in Japanese Patent Laid-open Publication No. 2000-025566.
The D-ring, which is designated by reference numeral 10 in FIG. 2, includes a body 12, and a roller 14 mounted to the body 12.
The roller 14 includes a fixed roller body 15, a rubber layer 16 formed around a peripheral surface of the fixed roller body 15, and a plastic layer 17 formed around a peripheral surface of the rubber layer 16.
The rubber layer 16 and plastic layer 17 are adapted to reduce frictional force generated from the webbing 1 when the webbing 1 comes into contact with the plastic layer 17.
The body 12 is circularly bent at one end thereof so that the roller 14 is held by the bent portion of the body 12. In the state in which the roller 14 is held by the bent portion of the body 12, screws 18 are fastened to the body 12 through the roller 14. Thus, the roller 14 is retained in the body 12.
Although the conventional D-ring 10 uses the roller 14 for reduction of frictional force, it still has a problem in that the roller 14 comes into frictional contact with the webbing 1 during the retraction and protraction of the webbing 1 through a slot 11 formed at the body 12, thereby interfering with the retraction and protraction of the webbing 1.
Furthermore, the conventional D-ring 10 requires an increased number of manufacturing processes due to the provision of the roller 14, so that an increase in manufacturing costs occurs.
Since the roller 14 is retained in the body, 12 by means of the screws 18 in the conventional D-ring 10, it is also necessary to use a process for fastening the screws 18.